We often get asked about what's better between SP400/500/600, or the SPS4/5/6 plugs, etc. The primary difference is the diameter of the hole the cable goes through. So, it mostly impacts which type of cable you use with it.  The next logical question is, "What type of cable should I use?"  Regarding cable choice, there are many potential considerations.

One consideration is weight. Larger diameter cable is very slightly heavier than small diameter cable. That won't matter to the vast majority of people, but can matter greatly for a touring musician with a larger pedalboard, especially if they fly to gigs.

The second consideration is how the cable capacitance will impact your tone. The tone of a guitar with passive pickups changes depending on what else is in the signal chain, the cable being one factor. Cable resistance actually has little impact, because the resistance on a guitar's amp input is actually extremely high (generally 1,000,000 ohms). So, the effect of <1 ohm per 10ft of cable is absolutely negligible. The real impact comes from a cable's capacitance, but that's also where there's controversy. Capacitance will not only impact the amount of highs getting through (when combined with resistance; aka longer cables), it will also impact the resonant peak of the pickups. That's why different cables, or even just different lengths of the same type of cable, can make a guitar sound different. But, there is no clear cut explanation for what is "best" here.

The classic workhorse cable of the industry is good ol' Canare GS-6. They advertise it as a "low capacitance" cable. However, if you compare it to most other guitar cables in the industry, it is much higher than average. At length, it reduces highs quite a bit and lowers the resonant peak of a passive pickup. In contrast, you can get ultra low capacitance cable these days that have minimal impact on either. The truth is, neither is the "best" option. Most people play through cable with higher capacitance for most of their playing life, and they don't even know it. They've dialed in their sound to suit that cable. If they decide to switch to ultra low capacitance cable, they'll suddenly be tinkering with their sound trying to dial out harsh highs that didn't used to be there. Or, if they started out with low capacitance cable and switch to higher capacitance cable, they'll suddenly think that their tone is muffled and missing the sweetness it had before. It's all a matter of perspective, based on the player's previous experiences.

The third thing to consider, that I think often gets missed in these discussions, is shielding. Low capacitance cable generally has low capacitance because it has less shielding. Less shielding means a higher chance of interference and microphonics. More shielding generally means higher capacitance and a stiffer cable with less flexibility. They may be unaffected by the outside, but they'll be heavier, tougher to work with, and will drain the high end on longer cable runs. It's all a balancing act, based on the needs and preferences of the end user.

In my opinion, unless you have a fairly large pedalboard and/or some long cable runs (to and from the amp and effects return across the stage), the impact will be fairly minimal (if noticeable at all). We offer our own mini cable.  It has a 4.8mm diameter, making it a perfect fit for 500-series right angled SquarePlugs, or the SPS5 straight plugs.  It will work with the SP400/SPS4 as well, but is a more ideal fit for the SP500/SPS5.

Unless people are after a certain preferred brand because they've succumbed to the marketing, that should cover the needs of pretty much everyone, and at a highly competitive price.