I haven't had trouble with AHCI/IDE issues with motherboards using AMD's SB700 and SB800 southbridge series unless there were BIOS issues to be resolved with an update. I had more trouble with older Intel motherboards back then, but YMMV. AHCI should be set active in the BIOS prior to installation and needs no special drivers for Linux. MEPIS8 worked well for many years - so well my 81 year old Mother refused to use Windows! (She started with a P75 Win95 box to prepare tax returns in 1995, swapped her hardware to a PII 400 running Win 98 in 1998, and (no longer running her own tax preparation business), switched from Win2K to SimplyMEPIS using the LiveCD in 2003!)
SSDs have native TRIM support from kernels => 2.6.33 so you'd be missing out. Even if you don't Trust SSDs; they work great for boot drives and swapping - but upon refreshing my memory I don't put much faith in the TGP either, and I resent taking choices from consumers to promote further escalation of DRM and vendor lock-in!
However, some time ago I decided on a different approach when I discovered the improved performance, feature sets, and reliability of newer kernels even though there was little security impact for me THEN. Much of the newer software cannot be supported by older libraries, even Firefox. MEPIS 8.5 handled a DOS "attack" from a misconfigured phone company router far better than a befuddled MEPIS8. As ISPs are forced to move forward with IPv6 replacing IPv4, IMHO, now is NOT the time to limit yourself to a kernel over 4 Years Old. Though ISPs still frequently use IPv4, newer home router/modems are compatible with IPv6. Newer versions of Windows, OSX, Linux, and UNIX all support IPv6 natively; and even Linux (which has supported IPv6 for years) has received many updates.
MEPIS11 hails from Missouri (Warren Woodford) and even has commercial versions, so he definitely understands privacy and TRUST issues. Beyond that, with the new UEFI Secure Boot issues, as much as I hate the prospect, I'll eventually delve into more current software with Sabayon backed by Gentoo and learn how to compile properly in my quest for independence - YMWV. There have been many hardware improvements since then; and software support always lags, but is far more useful now. A stable software foundation to build on that I trust (not Microsoft, Intel, or even AMD) is more important to me than bleeding edge performance, though UEFI Secure Boot is still a concern. VMs and WINE will let me use the required legacy software to support old hardware and alleviate some security concerns. Newer hardware with AMD-V and AMD-Vi are often required by my preferred software, (I prefer cores to games, and Intel's "Product Feature" and pricing matrix is mind boggling), so pre 890FX chipsets and old kernels are not for me. However, I plan to avoid Intel's new vPro and Small Business Advantage like the plague they are as railed against here.
By consolidating many old computers with dated software onto fewer, newer, faster, yet more energy efficient technologies, I can run support "obsolete" hobbyist hardware, (amateur radio and astronomy), and old family data, while enjoying more modern capabilities enable by recent hardware and software developments.