Portable units are the least efficient. Some people have no problems with them but most do. They just can't handle a grow environment. Do a search in the forums and you'll see for yourself.
The link that Jenn posted, I bought a mini split from them (Amcor). Here's the deal, parts for them are almost impossible to find. A fellow member here whom I'm very close to knows what I'm dealing with right now with that company. STAY AWAY FROM ANY AMCOR (Amcoraire) PRODUCT! They do not stand by their warranty. Window units are the cheapest bet. They're so cheap that fixing a broken one is a waste of $$$.
whats the cause of the high temps dude? Is it just high ambient temps, where do you vent the exaust for you little hobby? i've never heard of the temps being that high with T5's....... seems like there may be an underlying problem with the configuration of the set up.....