My experience with a cheap 64GB SSD (Kingspec) is completely different. I replaced my laptop's original 5400rpm Hitachi HDD with it. The boot time was reduced from circa 25s to 6s and most programs start without noticeable delay. And this is with low end SSD that connects to PATA interface. Boot performance seems to be mostly about low times for seeks and small reads in which pretty much any SSD runs circles around mechanical drives (seek times are generally 100-200x lower on SSDs). Low total bandwidth of the interface is really non-issue for most of my use. (no large copy operations between drives)
Did you align your partitions to the erase block boundary? Otherwise your SDD performance could be severely degraded as the drive has to do two read/modify/write cycles when one would suffice. These things (or the partitioning tools) are not yet plug and play.
Ted Tso has written informative article about aligning FS to erase block size, which can be found here