Sure is a "nice to have" feature.
Nice job... but I'm so glad mine came fitted - it looks a real mission to retro-fit the aux. heating!
I
have added the remote - not the OEM T90 but an aftermarket remote. Works well - I click the fob button while I finish my breakfast and 15 mins later I get into a warm-ish car with the engine coolant at 30DegC. already.
You need to watch the battery usage when using it remotely (with the engine off). The factory system (and your retro-fit, I assume) should kill the aux. heating before it pulls the battery down too low to start, but I haven't tested that! I only ever run it for 15-20 mins then go for a decent drive.
*edit*
alex_j, you might want to grab a Sharpie marker and cross off "diesel" on the Thermotop unit!
