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To summarize WPXM352’s excellent response to your question… One of your club members is an expert the other is not.

Despite what Midland Marketing would like the world to believe, by marketing non compliant radios, GMRS is wide band baby. The modulation is +/- 5.0 KHz, the channel bandwidth is 20 KHz and the channel spacing is 25 KHz. Example 462.600 and 467.600 MHz. The exception are the GMRS interstitial channels at 467 MHz which are narrow band +/- 2.5 KHz, on 12.5 KHz channel spacing. Example 467.5875 MHz when used by GMRS radios. All FRS interstitial channels 462 and 467 MHz are narrowband. Example 462.5875 and 467.5875 MHz when used with FRS radios. Wide band is what the God of FM Radio Major Edwin Armstrong intended: https://en.wikipedia.org/wiki/Edwin_Howard_Armstrong#Wide-band_FM_radio Wideband is tremendously better than narrowband: 3 dB better which translates to much greater area reliability. If you have a narrowband radio trying to use a wideband repeater or simply talking directly, the loss is greater ~ 6 dB. YOUR REPEATER SYSTEM WILL PERFORM MUCH BETTER IF ALL COMPLY WITH WIDEBAND AS INTENDED. THERE WAS NEVER AN FCC NARROW BAND MANDATE FOR GMRS NOR WILL THERE EVER BE AS FRS ALREADY OCCUPIES THE INTERSTITIALS. See the maps wide vs narrow. Green good, yellow nope. http://www.leikhim.com/page13.php FCC Rules: § 95.1773 GMRS authorized bandwidths. Each GMRS transmitter type must be designed such that the occupied bandwidth does not exceed the authorized bandwidth for the channels used. Operation of GMRS stations must also be in compliance with these requirements. (a ) Main channels. The authorized bandwidth is 20 kHz for GMRS transmitters operating on any of the 462 MHz main channels (see § 95.1763(a )) or any of the 467 MHz main channels (see § 95.1763(c )). (b ) Interstitial channels. The authorized bandwidth is 20 kHz for GMRS transmitters operating on any of the 462 MHz interstitial channels (see § 95.1763(b )and is 12.5 kHz for GMRS transmitters operating on any of the 467 MHz interstitial channels (see § 95.1763(d )). (c ) Digital data transmissions. Digital data transmissions are limited to the 462 MHz main channels and interstitial channels in the 462 MHz and 467 MHz bands. § 95.1775 GMRS modulation requirements. Each GMRS transmitter type must be designed to satisfy the modulation requirements in this section. Operation of GMRS stations must also be in compliance with these requirements. (a ) Main channels. The peak frequency deviation for emissions to be transmitted on the main channels must not exceed ± 5 kHz. (b ) 462 MHz interstitial channels. The peak frequency deviation for emissions to be transmitted on the 462 MHz interstitial channels must not exceed ± 5 kHz. (c ) 467 MHz interstitial channels. The peak frequency deviation for emissions to be transmitted on the 467 MHz interstitial channels must not exceed ± 2.5 kHz, and the highest audio frequency contributing substantially to modulation must not exceed 3.125 kHz. (d ) Overmodulation. Each GMRS transmitter type, except for a mobile station transmitter type with a transmitter power output of 2.5 W or less, must automatically prevent a higher than normal audio level from causing overmodulation. (e ) Audio filter. Each GMRS transmitter type must include audio frequency low pass filtering, unless it complies with the applicable paragraphs of § 95.1779 (without filtering). (1) The filter must be between the modulation limiter and the modulated stage of the transmitter. (2) At any frequency (f in kHz) between 3 and 20 kHz, the filter must have an attenuation of at least 60 log (f/3) dB more than the attenuation at 1 kHz. Above 20 kHz, it must have an attenuation of at least 50 dB more than the attenuation at 1 kHz.

I think the core argument comes down to the fact the FCC has described the channel uses for GMRS repeater (and other main) channels as: having an authorized bandwidth of 20 kHz and a peak frequency deviation not exceed ± 5 kHz. However, the regulations go on describe § 95.1771 GMRS emission types. Each GMRS transmitter type must be designed to satisfy the emission capability rules in this section. Operation of GMRS stations must also be in compliance with these rules. (a) Each GMRS transmitter type must have the capability to transmit F3E or G3E emissions. ( Only emission types A1D, F1D, G1D, H1D, J1D, R1D, A3E, F3E, G3E, H3E, J3E, R3E, F2D, and G2D are authorized for use in the GMRS. In practical terms the only two useful types are F3E (FM Voice) and G3E (Phase Modulated Voice), which are essentially the same to the receiver. The other modes allow for AM and SSB and limited data, as permitted in the regulations. Personally, I have never heard on anyone operating AM or SSB on GMRS, but I guess it could happen. So, the FCC has defined maximum channel bandwidth, deviation and transmission types. But, here is the issue, they have not mandated those. So, it is totally permissible to operate narrow band (NB) on any GMRS channel. Now, in practical marketing terms, any company that only markets NB units for GMRS is obviously not going to push or promote wide band (WB) usage. However, since some GMRS channels are designated as NB, it is unlikely a WB only radio would be marketed as it could not transmit on the interstitial channels. Which brings us back to the two experts. In fact, if the statements of the two experts have been reported accurately, the answer should logically be neither or both. If by "is" they mean can be used as, they are both correct. However, if they mean is mandated as, then both are wrong. In fact, I would now say a true expert would not have defined GMRS in such a way and would have offered a better description as is provided by Part95E and the responses to the original question. So, in my mind, the answer is neither expert is correct.

I've asked this before. Why can't somebody make a GMRS mobile radio that is 25 to 40 watts, works like we want for $150? And is part 95 certified? 1. Clean, on frequency emissions. 2. Wide or narrow band. (Narrow band to work best with bubblepack radios.) 3. Split pl tones for tx and rx. Or just squelch. 4. Multiple channels for the same repeater channel to allow preprogramming of pl tones for a trip. This doesn't sound like rocket science. Just an observation, I do not have an amature license. At the present, I am not planning to get one. I don't know any one with an amature license in my area. Radios don't do much if you don't know any one to talk to.