I agree, the all in one units are trouble.
I am in an awkward situation at the moment, as my MBT250 control unit decided to quit on me, and I was thinking about getting the Circuit Specialists' TH desoldering station as I have a fair number of iMacs whose caps need changing, and the customer will be phoning about them by the end of the week. After that I'll just repair the control unit, but now there is no time.
In another thread I tried getting info about easily available desoldering stations with a straight handpiece (like my SX90 Sodr-X-Tractor), but I am quickly running out of time and am getting desperate enough to get the CS unit, gun-shape handpiece and all.