I haven't seen any Columbo episodes recently enough to form an opinion on this, but you make great points as to why you often prefer the 90 minute ones!

As I started reading, the one where he plays with the studio graphics panel came to mind, but then I see you already beat me to it! :)

That portion annoys me so much. I love Columbo and will rewatch every episode many times without ever getting tired of it, but I always have to FF through that part, with much gnashing of teeth!

Firstly, the longer episodes aren't actually 2 hours in real time, but that's a detail.

I don't think the longer episodes are necessarily worse overall, but they're perhaps more variable in quality, both when comparing different episodes (Swan Song, Negative Reaction and A Friend in Deed on one hand, Commodore and Make Me a Perfect Murder on the other), and between different scenes in the same episode. And at least the poorer short episodes have the advantage of being over quicker!

I do agree though that there's unnecessary padding in many of the otherwise good longer episodes. I'd include the extra 'short hair' scene in Etude in Black in this, as well as that notorious graphics scene in Make Me a Perfect Murder, perhaps the most extreme example. These episodes would be stronger with those scenes removed.

I think this is the sort of thing that makes me tend to prefer the shorter episodes, but only slightly - some shorter episodes would be better off longer, and some longer episodes better off shorter. They probably got most of them about right.

The following two-hour episodes are among my favorites of the entire series:

Prescription: Murder
Ransom for a Dead Man
Rest in Peace, Mrs. Columbo
Negative Reaction
Agenda for Murder

Wow, I didn't realize that scene in "Make Me a Perfect Murder" struck such a sour cord with other viewers, as well! And I definitely agree that "Ransom for a Deadman" is one of the best, even quintessential, episodes. I'd have to say that I actually like "Last Salute to the Commodore", though. I think the script by itself is pretty lousy, but the fact that you have Falk,Vaughn, and the others delivering their lines with such delightful eccentricity makes the banal story glow with a certain charm it wouldn't otherwise have had.(Although I know I might be in the minority here)

I've always been attached to "COMMODORE" for the same reasons (and some others).

Glad to know there are others fond of "Commodore"!