I was thinking of this Quark:

But I recognized Conrad Janis from Mork and Mindy!

and was funnier at the time. However, I did like the complaining robot. Makes me wonder if Douglass Adams had seen it, too...

I think that Garak was far more interesting. I think the following bit of dialogue with Dr Bashir sums him up

Bashir: What I want to know is, out of all the stories you told me which ones were true and which ones weren't?
Garak: My dear doctor...they're all true.
Bashir: Even the lies?
Garak: Especially the lies.

He shows what a skillful operative he actually is in the episode "In the Pale Moonlight" in which he plants fake evidence on the corpse of a Romulan official that is certain to bring the Romulans into the war against the Dominion, and sums it up perfectly with

That's why you came to me. Isn't it, Captain? Because you knew I could do those things that you weren't capable of doing. Well, it worked. And you'll get what you want: a war between the Romulans and the Dominion. And if your conscience is bothering you, you should soothe it with the knowledge that you may have just saved the entire Alpha Quadrant. And all it cost was the life of one Romulan senator, one criminal ... and the self-respect of one Starfleet officer. I don't know about you, but I'd call that a bargain.

But Quark way more funny and frankly under his veneer of greed, and cheating his own brother, and always trying to get one over on people, was actually pretty kindhearted. I used to hate him as a one dimensional greedy asshole, but upon re-watching the series, he is way more layered and likable. In fact, he has done a lot of nice things for Kira and she won't give him any slack.

Whereas Garak, well, he used to torture people. Not nearly as likable. Can be super funny and witty. But not as funny as Quark.

I though the Roswell Episode was the funniest Star Trek Episode I have ever seen.

Quark is the creepy jerk with the heart of gold.
Garak is the creepy double agent with the heart of . . . well who knows exactly?

I like hearts of gold.

While I found Garak more interesting. You pays your money and you takes your choice.

Some of the Ferengi episodes though, dear God...

There is no defense for that weirdness.

http://www.agonybooth.com/recaps/Star_Trek/Deep_Space_Nine/Profit_and_Lace.aspx

that every Ferengi-based episode sucked. I agree many of them sucked, but "Little Green Men" was hilarious!