I think it really comes down to personal preference. But for practicality and cost savings, i think the best possible thing you can do is just use a computer monitor. A nice 21inch CRT can be had off ebay for less then 200$ (ive gotten 2, one for my cab and one for my room), with that you dont need to buy an arcadeVGA card, you get very high resolution and BETTER graphics than an arcade monitor.
Now some people will say an arcade monitor is better because its truely what the game looked like, well this is where personal preference comes in. Do you care about authenticity that much, where you really are seeing the graphics in their "true" form which is lower res. or would you take advantage of our modern technology , which if available then they would surely use, and view your games in a nice 1024 or higher on a PC monitor?
Truely no one option is better but ill put it simple
500$+ for that arcade monitor - arcade "true" graphics, +$ for AVGA card
200$ for a PC monitor, higher res, no AVGA needed, easy to install