DrugBuyers.Com: Tramadol - Long Term Safety?

I've been using Tramadol ocassionally as an alternative to using the Canadian Over The Counter Tylenol+Codeine+Caffeine tablets for occassionaly moderate pain. I've been really happy with this drug. It's a very effective pain killer but doesn't feel addicting as the onset is very gradual. I've read recently about the anti-depressent effects this drug also has. I would admit that I now find myself reaching for this drug more often instead of even just the plain Tylenol for mild-moderate pain. However, I've never taken more than 50mg in a day, and I'd say I've averaged over the past two months taking this drug 2 days per week, maybe 3 days per week at most.

I'm curious about two things, I'd assume taking 50mg a day only 2-3 days a week doesn't really pose a significant addiction/dependence potential. It seems the horror stories for withdrawl from this drug come from people either taking at least 50mg every day for an extended period, or those of have taken large dosages for a short period most of the time 150mg or more for several days.

The thing I am worried about though is the long term effects of this drug regarding its anti-depressent properties. I didn't choose this drug for those properties but am wondering if maybe I am unintentionally becoming slightly addicted to it even in these low, inconsistent dosages? I don't think so but I'd be curious to hear other people's experience in similar situations. It seems that 50mg of this stuff would have anti-depressent properties equivalent to very very low doses of drugs that are designed primarily of anti-depressents right?

Also, I've scoured the Internet and could not find any BAD research results on the use of this drug. It seems the scientists/doctors having nothing but good things to say about this drug especiall compared to the other pain killers. The only bad mark against it is the potential for seizures at higher dosages (I think 150mg and up) but this seems like sort of a built in safety factor.

Now just the other day, they say Naproxen (Aleve) can be bad for the heart so now there's one less choice for OTC pain killers out there.

Does anyone know of any information that indicates there can be siginificant potential for negative long-term effects of low dosages of Tramadol? Because I don't see any reason to use Tylenol anymore for occasional pain if I've got this stuff around. I know I still need to use Ibuprofen if I want anti-inflamatory effects.