I don't have a tandem kayak but have used one, in fact my dad and brother rented one this weekend and loved it, it was their first time out let alone fishing from one. There are lots of options out there, I wouldn't recommend spending the extra money getting the flush mount rod holders installed. Most kayaks now have them already there!! If you plan on taking kids out on it I definitely don't recommend a sit in one. If it does happen to tip, you don't want to worry about them being stuck, besides that, sit on tops are typically more stable due to their width. Here are some good options:
Ocean Kayak Malibu 2XL
Wilderness Sys. Tarpon 130T
Native Watersports Magic 14.5 (best but most expensive...IMO)
Native Ultimate 14.5
Future Beach Nexus 160T
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