I wouldn’t bother with Implants at this stage of the game, the difference in training time is marginal unless you want to spend more than your budget just on learning implants.
Basically SP ticks into your head at a set rate (x per second or whatever) and you can install implants that increase this rate by a %. You have various Attribute points that also effect the trickle rate of SP, and if you look at a Skill’s Show Info window it will list 2 attributes that effect the skill training. So for instance most weaponry skills use Perception and Willpower. This means that to train weaponry skills at the maximum rate I want a high score for Perception and Willpower. Various implants give a certain bonus to these attributes with +1’s being cheapest and +5’s being the most expensive. You can also periodically remap your characters points, though these are finite and quite rare so be careful.
Here’s a quick quote from a Wiki that explains things well :
"Each attribute enhancing implant boosts a particular attribute, with some of the best (and rarest, and therefore most expensive) ones giving additional bonuses.
There are 5 “simple” implants for each slot: Limited (+1), Limited-Beta (+2), Basic (+3), Standard (+4), and Improved (+5).
Each slot enhances a different attribute as follows:
Slot 1 - Alpha - Ocular Filter: Perception
Slot 2 - Beta - Memory Augmentation: Memory
Slot 3 - Gamma - Neural Boost: Willpower
Slot 4 - Delta - Cybernetic Subprocessor: Intelligence
Slot 5 - Epsilon - Social Adaptation Chip: Charisma
Note: “Simple” implants (those that only boost attributes) do not use Greek designations."
Hope this helps. It’s probably not worth splurging on pricey implants yet, since you will likely lose them before you gain any decent benefit.