Compare ISA vs SIPP for Long-Term Saving

You have money to save long term and the choice between an ISA and a SIPP turns on tax treatment, access rules and your own plans for the cash. This compares both for your tax band and intended use, explaining the trade-off between tax-free flexibility now and the pension top-up you cannot touch until later. A real answer, not a generic one.

<context>
You have [monthly amount] to save for the long term and are deciding between putting it into a Stocks and Shares ISA or a Self-Invested Personal Pension (SIPP). You are a [basic / higher / additional] rate taxpayer and your intended use for the money is [retirement / possible early access / uncertain].
</context>

<task>
**Compare the ISA and SIPP for your specific situation:**
1. Explain the tax treatment of each: in vs out, and what that means at your tax rate
2. Model the difference on a £10,000 contribution over 20 years using a consistent growth assumption
3. Address flexibility: when and how can you access the money?
4. Explain the pension lifetime allowance status and any relevant annual limits
5. Give a clear recommendation or a hybrid split with rationale
</task>

<output_format>
- Tax treatment comparison (table: Feature | ISA | SIPP)
- £10,000 worked example (contribution, tax relief, projected value)
- Access rules comparison (plain language, one paragraph each)
- Recommendation with rationale (one paragraph)
</output_format>