The verdict
If you send many proposals and contracts and want one tool for creation, signature and tracking, I'd pick PandaDoc. It has a free plan, and the template work pays off with reuse.
If the proposal is a real part of your sales process, your CRM is HubSpot, Zoho CRM or Pipedrive, and the page format will help close deals, I'd pick Qwilr.
Watch the plan structure on both. Qwilr's Growth and Scale plans are annual with minimum seat counts, and API access and automatic generation use credits. PandaDoc's cost grows with seats, so begin with a pilot team. Neither wins outright. Build the same proposal in both and let your buyers tell you which they prefer.