I seem to recall reading somewhere that for a pressure gauge to be the most accurate, regardless of brand, that the target pressure needs to be in the middle of the scale on the pressure gauge. Based on this, a gauge with a scale of 0-80 would be more accurate for a V2 (where front is 36psi/rear 42psi) than say a gauge with 0-50 PSI because it is near max range or 0-100 PSI because it is the low side of the range. I haven't tested this, but it makes sense to me. That said, I use a 0-60psi gauge and I haven't had any issues at all.
You can spend as much or as little as you want on a gauge depending on quality, precision, options, country of origin etc. The gauge I use is made by Joe's Racing. Made in USA, analog dial type, 0-60 PSI with bleed valve, swivel, 45 deg angle, and about a 12" hose. It wasn't cheap, and I could probably get along just fine with something from HF, but I don't buy my tools more than once - unless I lose one of them. That's just me though.
There are several different options out there - Digital, Analog Dial, and Stick. As far as function goes, I don't know if one is better than the other; maybe one of the Troopers with more experience than me can chime in. I do have my own perception that the analog dial type might be better, but nothing to back up that claim.
Something else to consider is an offset valve stem. Amazon has an 87 deg black billet aluminum valve stem, made in Italy if I recall, that works well. I put them on my last bike at the same time I replaced the tires, and never had an issue to checking or filling the tires.