Yes, I have considered that, but from what I've read the company is excellent on replacing bulbs with better ones.
The company (HTG) is excellent AND they give excellent service except through emails,be forewarned that if you have a problem you need to break down & call them,i did & got instant results.
I have thousands of dollars worth of htg gear & i have just as much more expensive brand gear (Sunlight supply) & i got just as good of service from both,blaming any company for a broken bulb that is delievered from ups or fedex is an uneducated slander,fedex & ups kill & destroy thousands of packages daily,especially light bulbs.
When comparing ballast design from htg & sunlight i prefer the htg design,its design alows heat to dissapate very quickly away from critical components within the ballast,with any electronics heat is the number 1 killer.
On a side note digital ballasts may not be the route you want to take,the savings are not huge at all,were talking small percentages here,no massive savings will be realized on your monthly bill with one or 2 lights,there is also the lifespan factor,a standard magnetic ballast will last 20 years,digital ballasts are well known for short lifespans & have a much higher failure/break down rate over magnetic ballasts.
As for listening to people bad mouth htg just look at their ebay feedback,over 5,000 people have spoken & ALL ARE BUYERS OF HTG gear,before listening to anybody on any forum praise or bad mouth any supplier ask them if their comments are based on ownership or mere repetition of what others have said.
Ive seen some valid problems associated with htg but there are no different that what any other manufacturer will experience only htg is the #1 internet grow shop so they stand out more.