A couple of thoughts...don't the SCD-1 and VTL monos both allow balanced cabling? The SLP-05 is balanced while CJ gear, including the CT5, is single-ended only.
The SLP-05 uses 6SN7 tubes, which have their own distinctive sound when used in a preamp. You might want to read up on general differences in sound between 6SN7 and 6N30P tubes...not saying one is better, but I have had both and IMO they do offer different sounds.
The SLP-05 is tube rectified, which the CJ is not - and many prefer the sound of tube rectification.
The SLP-05 uses an ALPS motorized remote potentiometer for volume control. The CT5 uses a more sophisticated volume control, described as
All control functions of the CT5 operate through microprocessor-controlled relays. For the level control, the relays select combinations from a network of precision, low-noise metal foil resistors to effect loudness and balance changes in 100 steps of approximately .7dB per step. All switching and adjustment can be controlled by the units remote control.
Personally, I will never again own a preamp using an ALPS (or ALPS style) potentiometer as a volume control. IMO, they are noisy compared to discrete volume control solutions and it is well known they commonly do not track as evenly between channels. It is not unusual for this channel to channel imbalance to be significant over the lower range of control.
Although many report liking the sound of the SLP-05, I would personally choose the CJ, given the choices. However, the only way to know for sure is to listen to both. Good luck.