I prefer trade collections. It was a sequence of TNG comics that lead me to blacklist comics for a long while: a four-part story featuring the return of the Borg, called The Worst of Both Worlds. I started collecting them, and then they got to the final part, promised as an extra long issue, celebrating that it was #50. And everyone bought it out. It was gone when I came to find it. I'm sure there are reasons, but I don't care, I was livid. I still don't care. I hate comics in their individual issue format, hate them! It was something like 10-15 years later that I stumbled on that final issue to complete the story, and I put the thing back and walked away.
It was only Star Wars that made comics something I felt I would dabble in again, and that was when I was able to get the Dark Empire story in a single package.
For a long time, my only comic collecting has been in trade form. I have made a few exceptions in more recent years. One exception was the comic adaptation of the rough draft for George Lucas's script, The Star Wars, which is so different from the original movie. I made an exception with that series because there was doubt that it would get a trade collection release. I made damn sure I got every issue, collected with angry fanaticism. When it was release in trade, I got that to replace the individual issues.
The other exceptions were my return to the world of ST comics. I got the DC TOS volumes 1 and 2, when they continued to not get trade collection releases. Being able to find large batches of them collected together on ebay, with no missing issues, broke through my blacklisting of the format. And sometime last year I found a new comic shop I had never visited, and the had all the DC TNG comics lined up; the shop owner was willing to work with me and arrange things so that I could buy them at over the course of a couple of months and help make sure they wouldn't disappear.
Making my way through DC TOS Volume 1, I have gotten in the groove of reading the letters column, which is an interesting window into how fans reacted to the series at the time. It's almost like visiting and lurking in a fan forum and reading fan commentary about the state of a franchise nowadays. That's something that is kind of fun, but it's not major. I'm not a huge fan of all the advertising pages that are loaded into those individual issues.
Effectively, though, the individual issues format is still blacklisted in my book. The rare exceptions are a mark of how much I wanted a series that has never been made available in trade (or omnibus collections). The DC TOS volumes never having been collection in trade or omnibus formats is wrong. I would get the Eaglemoss collections, but I would prefer them in paperback...that is one case were my mind says, "I already have them."