We use square currently, it was cheaper for us if we do less than $3,000/month, plus no contracts, unlimited readers and can be taken anywhere internet is ava. including the phones..... so it is one account for 1 store, 3 onsite techs, and occasionaly trade shows etc...
One thing though.... square has almost ZERO customer support.... so you may want to give gopayment a go, also if you are pushing more than 4,000 consistently every month a traditional setup will be cheaper.
Another thing, at least with square if you run more than $1,000 of entered cards (not swiped, keyed in) in 30days they will put any thing over that 1,000 on hold for 30 days, so keep that in mind.
It works good for us as we are mostly cash/checks, and only do 1500 - 3500/month in CC sales.