I have real world experience with them and wouldn't recommend. Their website says that systems can be returned at the customer's expense but when you check out with PayPal, it says the kits are non-returnable and they try and stick by that. I ordered from them when I first started my AC project in April and immediately had buyer's remorse. The kit was basically a Hurricane Air setup (with its controls) that replaces both the heater core and evaporator/expansion valve, full size hoses with fittings, a Sanden 508 knock-off, a small condenser, small condenser fan and a drier; the instructions were unfathomable. Dtech was straightforward in that they said the instructions were written for 2002 installations and they were working on E9 instructions. I convinced them to let me return everything since it was all unopened but at a very steep restocking fee (embarrassingly steep but I knew I wasn't going to use it). And the shipping was pricey too. Live and learn.....
So I bought everything a la carte: real Sanden 508, the biggest condenser and SPAL electric fan I could cram into the front of the car, a large drier and then made my own hoses and fittings (using the reduced barrier hoses and fittings which are a LOT easier to deal with in the E9 confines). Plus you can run the hoses, THEN put the fittings on inside the cabin instead of trying to cram the fittings through the firewall opening with the hoses attached. I bought an evaporator and expansion valve assembly from Blinkling here on the E9 Forum. I think all of that was probably less than $800, definitely less than $1,000. Then put it together myself. It's not hard but you have to be patient and learn some new skills, which for me was not a problem. I just did another post where I reported I was getting vent temps down to 29-30 degrees, so this setup will definitely work and it uses all the original controls.
My two cents.