Either boat will do what you want, Just remember for all speeds not just at the dock you will most likely want to upgrade the steering system so you can handle water sports activities with ease, maintain control in rough conditions, wind and waves with confidence even control the boat while rapidly decelerating.
And for a faster hole shot and cleaner wake you would want to choose the deluxe version of my steering systems to get the plaining surface under the nozzles.
These patented steering systems are effective at all speeds and inexpensive, for either of the 2 boats you are considering.
The 19 foot would use the super ultimate ak-19 deluxe system, spring loaded aircraft aluminum , adjustable SUPER FINS provide adjustable all speed steering and the plaining surface to clean the wake behind the boat , the current buy direct discount price is only $268.99 for that complete setup and it also comes with free domestic priority mail. no plastic parts and does not increase the draft of the boat.
If you choose the twin engine 21 foot you will want to add the super magnum ak-19 deluxe system .
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It adds in the PATENTED second tie rod so you can balance out your twin engine system, while adding redundancy ,
It has adjustable tempered aluminum super fins on the outside and tempered aluminum top fins for extra slow speed steering assistance.
plus it comes with the plaining surfaces for a smoother ride in chop, a cleaner wake for water sport activities & faster hole shot .
This system will keep you in control in wind waves and current with extra control during rapid deceleration , both systems will also allow you to make high speed turns without the annoying high speed bleed off common with the stock setups. The specially designed Patented system combined with the factory rudder forms a V configuration for maximum effect without increasing the draft of the boat. The super magnum ak-19 deluxe is currently buy direct discount priced at $489.99 also with free domestic priority mail included.
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So choose the boat that suits your needs and your budget then add the most features and benefits to the steering system so the only thing you need to practice is SMILING when you drive it.