Siteuptime Vs. Hyperspin

I have been using siteuptime.com and they seem to be working well, but since I do a content check (making sure vBulletin and MySQL are working) and I want two minute checks, I pay two extra $5 charges, so it comes out to $15 to check my one site.

I read about hyperspin the other day and they do 2 minute checks (with content check - looking for keywords on page) for around $5 a month.

So, from a cost perspective hyperspin is a third of the cost of siteuptime for my needs (2 minute check, look for keywords).

I am curious about people that have used both. Are they both equally reliable? Has anyone had any problems with hyperspin?