"Best" is always relative and subjective with something like guitars, isn't it? I think it's more of a "what feature set do you like?" kind of thing. Especially with Guilds, compared to a couple of other guitar companies, because they never really had a universally-agreed-on dip in quality.
for the things I do, in a "one guitar, no keyboards" band setting, I loved my '62 X175 SO much I've looked for an identical one for years, and I eventually found one. My first one has a slightly slimmer neck and bigger neck angle, but otherwise the guitars really are the same, and I've had moments where I was forgetting which one out of the two I was playing.
If the band gets bigger, and there's rhythm guitar, and or keyboards, or more, the big, deep 17-inchers that the X175's are, are a little too big and bassy sounding, and don't always cut through like I want them to, so if something like that presents itself, I'll grab my '61 Starfire with DeArmonds. The smaller, thinner body makes for a lot less bass content in the sound, and the DeArmonds are loud, trebly, and agressive, and sit better in a bigger mix than my other Guilds.