With what you know now what components doe you wish you had bought years ago?

After all the biased advertising and sales pitches and after the smoke has cleared what components do you wish you had bought. My daddy would say with hindsight 20/20. With what I've read the G.A.S. Ampzilla comes to mind or a Hafler amp. Good solid word by mouth on the internet. The HK cassette deck CD491 is another I was actually able to acquire 8 years ago and was a solid performer until an electric fault came up. Ive read that shops that sold that and the Dragon compared the two side by side and the HK held its own or would I dare say sounded as good for half the price? I read one time it specd out better. Another one would be the Infinity Kappa 9 speaker. I had a ballsy enough amp to handle it.
KEF107. I had a chance to buy them at a ridiculously low price and didn't. Two weeks earlier, I had bought a new set of speakers, and decided that would not be right to take them back. What? Yah, I wish that I could relive that one.
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Higher efficiency speakers.  Starting down the road with higher efficiency speakers would have opened the door to less expensive, but excellent lower-powered amplification options, both tubed and solid state.  Not talking flea-watt 2-5 wpc power, but more like 20-50 wpc amplifiers and partnering speakers that can rock out within that power range.  
 @mitch2 +1.
I regret not buying Dunlavy SC IVa speakers.
I regret not buying Hales model two signatures.

My biggest regret is not buying an Audio Research SP-9 preamp when I purchased and ARC Classic 60 tube amp. Got an insanely good deal on the amp (which was less than two years old). The seller threw in (without my asking) a pair of 9 foot ARC Litz speaker cable AND two sets of ARC ICs (whew!). He offered me the preamp (can't remember the price) but I declined. I used instead some Adcom preamp I already owned which was hailed as a "giant killer" (it wasn't). The seller is still active (this was 1992 or so) and I purchased another amp about 10 years later. Wish I had that SP-9!
You know I always wanted a Tandberg stack, but having bought an amp not too long ago, it just didn't hold up.
In the 1980s I wish I bought a SAE stack that I was eyeing. Could have driven my AR speakers.
In the 2000s when I was making good money, I wish I went straight to an Atma-sphere S-30 or M-60s instead of trying various SS and tubes. I finally purchased a S-30 and am eyeing the M-60s.

Allison or ADS speakers instead of Bose 901's in the mid 70's. I had a friend who was in love with Bose, bought a pair and convinced me to do the same.
More efficient speakers.  Since the late 80's I've own nothing power hungry speakers and powerful amps cost powerful money.
I have/had the hafler DH 200 and 101 preamp. The hafler s--- is rock solid. I had wanted a bryston amp/preamp. Well, i found a bryston 1b- mc (built- in moving coil amp!) for all of $300.00 on ebay.

i have a pair of infinity 6kappa speakers. If i had to do it again. I would get the 7kappas.
Quad ESL, Eminent Technology LFT-6, Garrard 401, Garrott Brothers-modified Decca, Townshend Audio Rock Reference (this last one not from lack of knowledge, but lack of necessary $ ;-) .