Not yet, ive only owned PS systems and they all have been great, in fact i enjoyed them so much that i pre-ordered the PS4 the moment it went for sale on amazon, and im one of those first million PS4 owners.

and as for the PS4 ive enjoyed it quite a bit, although it didnt got as much use as my PS3 in 2014 that will change this year with the amount of games coming for it, starting with Bloodborne.

Nope. I know what I want.

For me.. PS3

I was already having xbox360, wii from that generation. What was the main problem ? Well there were too many:
1. The UI i didnt like (sorry, but i was really prefering the 360 ui - not the new one). On PSP i like it .. but PS3 - there it was just plain, uninspired, fadly and so one. the themes didnt help it either.
2. The games - i dont know why but same games plays better on 360. It goes about feelings - i still feels something odd from PS3 - like something dont touch or i will break or too crisp pictures.. so at the end it doesnt look like a game. Maybe i'm on a side of more western games and games on PS3 (even created by westerns) feels different what i used to play on PC or XBOX.
3. Screen tearing - ouch.. GT, Uncharted and so one.. i really hate this..
4. The ugly marketplace (ps store).. my opinion as the topic saying..
5. Updates - this was a pain in the ... just to wait half and hour to play a game ? Serriously ? No background downloading... a step down from XBOX .. really
6. The gamePad.. sorry folks, but xbox is really better in this (came from dreamcast gamepad).. ok.. i admit, that battery is better on this pad..

At the end.. the console is collecting dust .. but u know what ? It opens my eyes, and i really don't rush buying another console from this generation. Have to wait..

Yes, I regret buying PSP & DS last gen because I didn't play them much. I drive so can't play while commuting, and when I'm at home I prefer to play my consoles or PC, so portables don't get enough use and this gen I didn't buy either.

After that I don't really regret but generally disliked the Wii.  Outdated technology with motion gimmicks was not what I wanted video gaming to become, and fortunately neither did most people in the long run.

For current gen I don't really regret buying either PS4, Wii U or XB1.  PS4 is a treat in every way.  Wii U game quality is excellent, and the gamepad is great to play on without using the TV.  The XB1 has had a few great games, but is going to be a bit idle until QB, Halo 5 and (fingers crossed) next Gears of War come out, but I can't regret it because it was cheap, especially MS gave $100 trade-in for my really old XB360.

Nope! I always get some sort of enjoyment out of the systems I buy!

Wii and PS4

The GameCube. I got it after the 7th gen had started to be able to play RE and MGS remakes, but never got used to the controller so i sold it a week after. Luckily i only lost 5 euros

life is too short for regrets so no.

The PS3, the lack of good JRPGs killed the system for me. In fact, I should have skipped last gen consoles entirely. Vita is also a disappointment for now, but I bought it only 4 months ago so it still can get better, my main problem is that in these four months I only bought 6 games for it and 14 for the 3DS, and I don't own a 3DS...

Yes, the Gamecube. I wasnt getting as much bang for my buck, so I sold it and got an Xbox. Wasnt until then that I got Halo and Kotor and realized PC gaming had finally come full blast to consoles.