i completely agree you get what you pay for, how ever a $30 investment on a 10G nano/ temp tank is not bad at all, im actually buying a MH fixture this week for my 150G but as for now the GU10 will be sufficent- not the best but better than nothing.
Make sure the GU10s are well ventilated, we tried them and they were not ventilated enough and they actually started melting after around 6 months
29 gallon-planted community
20 long frag tank
75 gal-planted goldfish
75 gallon mixed reef with 20 gallon sump