They are well built. I don't see a problem with them not lasting - I had some of the very first ones.... no problem there. All parts are better isolated than the c's.
There were many 'tricks' to vaping eGo-t's and eGo-c's - most of them posted here.... I got good vapor (I'm all VG) and I was lucky with the c's or I did those things necessary to make them run well. I found the silicone caps helped with the t's but the hard caps better on the c's for some reason. Prepunching the tank was essential - or cutting off the 'chads'. Power vaping created too much internal pressure and would cause leaks. Slow draws were best. And LR's were just too much wattage, imo. Katya, Scottbee, me and a few other vets did well with them for over a year but we communicated to each other about problems. Vicki's (from cignot) cleaning and wicking videos helped.
I never got the plastic taste - my aversion is to metal and all of that may be genetic or just different buds firing
I've got more than 8 type A attys, which tends to reduce the overall cost. For you, it may not be worth it. While I have two cc's going and I DO like them and the flavor is great, I still prefer the Tabac BCC's for my other 5 flavors. I have a PV for each flavor.... When I tried the T2's, I changed all eGo-c's over to the T2's.. they were that much difference in 'fuss'. When the Tabac BCC's came out, I switched all over to the Tabacs, because of some problems with the T2's - mouthpiece threading (which was fixed later) and seals getting out of place, so you had to eyeball that on refills.... and the 'top coil waving' thing...lol. I won't be switching out the Tabacs for the eGo-cc's, but I'll keep the two cc's I have going.
On the plastic end piece on the mouthpiece... I never had a problem but had a friend who would always remove those - he bit down on the mouthpiece and almost inhaled one