Dont take it off unless you have thermal paste to replace the messed up, or nonexistent thermal paste already there. I really reccomend you just go purchase some thermal paste at the nearest store and redo it, it is usually very inexpensive.
Though if you're looking for a newer cooler, dont go for it yet. Redo the paste, your temps may drop by 20C at load, as your current temps right now are sortof insane. If you're still not satisfied afterwards, the H100i is the best of the bunch, followed by the H70 and the 212, but they're all very good.