Hi all you expectant purchasers. This is my experience of Tech4. Order taken and delivered on time in fact next day. Had a small problem with an ener-j wifi relay switch, indicator light not showing. Tried to contact Tech4 but they were offline at the time, it was 15.16 on Friday So sent an email. By 15.29 I had a reply with the advice I had asked for. Followed their instructions and 'volla' it's now working fine. The problem to me was the instruction manual that came with the wifi relay switch was missing more detail on fault finding and resetting the switch. TECH4 Excellent service as far as I'm concerned. Will be looking at them first for any other electrical bits and pieces I may need in the future.