When viagra alone stopped being especially effective, I also used a medical grade VED with a tension ring. Initial cost was expensive (over $200) but no ongoing cost. It was very effective, little prep time, no side effects. A year ago, I started using trimix injections. Those are like being a teenager again. Yes, it stings a little bit, but I use a tiny insulin needle. Cost is about $10 per injection ($120 for 5ml bottle, inject 0.3-0.5ml), no more than 3 injections per week. Also unlike viagra, little prep time, lasts a long time, and no side effects.
Best site for more information:
https://www.olympiapharmacy.com/product/trimix-injections/